US2447287A - Adjustable intraoral tracer - Google Patents

Description

Patented Aug. 17, 1948 ADJUSTABLE'INTRAORAL Tana En.

Fay E. Smith, Cleveland, Delmar'Lacer, Lakewood, and Clarion B. McLeod, Cleveland, Ohio,

assignors to Fay E. Smith,l )elmar Laccr, and Clarion B. McLeod, doing business as Smith,

Lacer,

McLeod Dental Laboratories,'Cleveland,

Ohio, a partnership of Ohio I v Application June 2 1947, S erial No. 757,144 f invention relates to the manufacture of dental plates, and more particularly towhat is known as an adjustable, intra-orail tracer, the purpose of which is to assist the dentist and laboratory technician in, so shaping and forming the plates as to insure. proper vertical spacing between the jaws and thus not only secure correct bite but also preserve or produce the most desirable'contour of the lips, cheeks and other soft tissues. I

One object of the invention is to provide an improved tracer of simple form, capable of repeated, use, and adapted for adjustment while the plate models are .within the oral cavity, .Another object is to. provide a tracer of the character described which is very compact, which may be molded in situ as a partof a bite plate, and whichtherefore is adjustable while in place in the oral;cavity. .Still 'another object is to provide a tracer including a stem vertically adjustable to determine proper-plate spacing, together with simple and eifective mechanism including a memberextending outwardly through the mouth opening for adjusting said stem.

Finally, anotherobject is to provide animproved tracer of such form as: to simplify-and improve the present technique in the construction' of dental plates, as will more ruuy appear hereinafter. I I 1 Furtherobjects of the invention'in part are obvious andiin part will appear more in detail hereinafter.

a In the drawings, 1

Fig.- lreprese'nts a sideelevation of a portion of the face; with the jaws closed, and showing the protruding operating shaft-of our improved tracer; g I Fig. 2 is a similar view, but with some of the soft tissues in section to expose the bite plates;

Fig. 3 is a front elevation of a pair of bite;

plates formed andequipped according to our invention;

Fig. 4 a sectional elevation on the line 4-4,"

Fig. 3, but showing the tracer in elevation;

Fig. 5 is a bottom plan view looking upwardly along the line 5-5, Fig. 3, and'illustrating the operating shaft in operating position;

Fig.6 is a plan View, looking d wnwardly 'along' the same line, Fig. 3; and v, Fig. '7 is an enlarged sectional view through the tracer along the line 11- 1, Fi 5. Q

The tracer forming the subject matter of the; present invention can best be explained by a. description. of the. technique of which it; forms 4 Claims. (o1.- ga -sa remote, from a part. It may be assumed, as an example, that a dental techniciamin his laboratory, possibly theoflice' of the dentist, is assisting in the preparationor fabricationof dental plates in accordance with measurements and other instructions obtained andsupplied' to him'by' the dntist'as' the result of his examination of the patients mouth. The cooperative procedure of the dentist and his technician is as follows;

First the dentist prepares a pair of upper'and lower jaw impressions in any suitable'plaste'r or other material, by standard procedure, requiring neither illustration nor detailed description. Next, he preparesthe usual'wax mush bite form (not shown) to simulate the .true bite rela?" tion 'of the two jawsyand also establish an arbi trary vertical spacing relation between them, as a basis from which to work later on, as will appear I I The twoim'pressionsandfthe mush bite form are sent to 'the technicia'n who proceeds as fol- First, he fabricates two models (not/shown), from the'two' impressions. one for .each jaw. The models are complementary to the upper and lower jaw impressions furnished by the dentist and simulate .the upper jaw and palate and the lower. jaw respectively of the patient. These models are mounted on the hinged arms of the, usualarticulator (not shown) by means of which they may be relatively moved to simulate ordi nary bite action. Base plate members are then made conforming to the models. The upper plate comprises an impression Ill similar to-the impression made by the dentist and includes an integral central. portion I [la ,across the palate. Ifhe lower plate comprises an impression ll adapted to fit the lower jaw of the patient. The plate members I0, ll, are temporary and may be made of any suitable material for the. purpose; such as a hardening plaster or a plastic material- Each is a thin walled concave-convex member accurately conformed to fit the corresponding jaw model member on its concave faceand: curved smoothly on its convex face.

Assuming the two models attached to the articulator, the technician adjusts the articulator arms to close the base members togetherupon the mush .bite form, thus bringing them into exactly the same bite relation existing when the plates l0, II as at I2, I20, and builds them up to convert them into bite plates. The built up wax supplies to the base plates material to temporarily take the place of the teeth to be applied later, and to support the soft tissues around the mouth and lips, and to limit approach of the two jaws, in the model, to a position just a lit-,

tle short of that where the teeth will be in bite in detail. This he accomplishes by imbedd ing the shank or head l5 of the tracer in wax or plaster Hlb applied to. the inner or concave .face of the upper plate member Ill as shown in Fig. 4.

He also applies or attaches to the lower plate member It, with wax or plaster, a thin flat metal plate I S, made for example of aluminum, and the upper surface of which may be coated with colored paint or other material to show scratch traces upon it.

All parts so far prepared are now returned to the dentist for further adjustment in the mouth of the patient.

But, before explaining that procedure, it may be well to here describe the particular embodiment of our tracer shown in the drawings solely for purposes of illustration, it being understood that the invention is not limited to this form but only within the scope of the claims appended hereto.

'The tracer M of course is quite small and compact, because it goes into the oral cavity and must not interfere with comfortable closing of the jaws. It comprises a body portion Ma of generally cylindrical form having a flat transverse face I! at one end and a reduced shank i8 at the other end provided with aflange'd head l5 by means of which it may be firmly and immovably imbedded in the securing wax or plaster. The body is hollowed out to provide an inner cavity 'or chamber 19 within which is mounted a tracer member 20, the lower-"end of which protrudes through face I! and is pointed, as at 21. The upper 'end of said tracer'lies within a reduced extension '22 of the chamber 19.

Suitable operating means is provided for adjusting the tracer member-29 longitudinally or endw-ise'in said chamber in such manner as to vary the positionof its pointedend. This *operating means may be'of any form, so long as the adjustment may be made while the tracer is within the oral cavity and does not interfere with-the form or position of-the soft tissues, such as the lips. The itracer member moves 'in a straight line which is approximately normal to the 'occlusal plane which isroughly indicated by the line 55 of Fig. 3.

In the form shown the tracer member 2D is 'a threaded screvv, longitudinally slott'edl alongone side 'toreceive the inner 'enizl of :a ihea'dlessset screw :23, which prevents rotation of the screw but-permits its endwise adjustment. On "the sorew is mounted an internally threaded nut or actuating member in ithesformof aibevel'gear 24 which meshes with -'a-.'similar gear 25 on the inner end of a shaft 26 rotatably' mounted on a hori-- zontal axis in a plug 12:1 driven into an =openingin the ibody wall. Shaft :ZS has a noncircular,

such as square, recess 28 in its outer exposed end to receive the like inner end of a key shaft 29 by means of which the gearing may be turned in either direction. When the tracer is molded into its 'fixed position it, of course, is turned to such position that the recess 28 is presented outwardly toward the mouth opening, preferabl in one of the ends or corners of the opening, and a hole -'or aperture 30 is cut out or dug through the wax opposite said recess.

'- "The purposeyof pur tracer is to enable the dentist to relatively adjust the bite plates of a pair, while they are properly co-related in the oral cavity, in such manner as to secure or determine that particular vertical spacing between said plates which provides or produces the desired, or them'os't'pleasing, appearance or external contour of the soft tissues, such as the lips. With age, the teeth wear down, so that later in life it may be desirable, in new plates, to appropriately increase the vertical spacing, While with the first set of plates it'is equally desirable to initially determine the best relation. In either case the best results are secured only when the adjustment is made while the bite plates are in the oral cavity. The plates and models, prepared by the technician, as described, are returned to the dentist. He inserts the bite plates in the mouth, as in Fig. 2, and pushes the square end of the key 29 between the lips and inserts it through opening 30 into the square driving recess 28, as in Fig. 1. Then he turns the key to adjust the tracer screw with its pointed end engaging the surface of the flat aluminum plate-16', as in Fig. '4. The adjustment is continued by movement of the tracer screw up or down to an optimum osition, in which the lips, relaxed or in repose, present the most desirable external contour or appearance, or where the bite 'is comfortable to the patient, or by the criterion of the individual dentist.

The patient is then requested to move his jaws as though to grind his teeth, the eifec't being to cause the tracer point 2| "to mark or scratch upon plate [6 an arched line, the gothic arch, the apex of which is at thecentral vertical axis of the jaws. This axis is usuallymarked permanently with a small hole 3i, Fig. 6, inte -whichthe pointed end of the tracer screw will extend.

After hole 3| is drilled the plates are again checked in the patients mouth with point 2zl fin hole'3l, and-readjusted, if necessary.

The operating shaft is Withdrawn and the bite;

plates are temporarily secured together, or in fixed relation b means of wax or plaster of Paris, and with them so secured, the two" plates,

as a unit, are removed from the mouth and returned to the technician in that condition.

He secures the bite plates to the articulator arms as before. This is accomplished by first mounting one bite plate, .say the lower, uponits base or body member, and then closing the other arm of the articulator, with the other body member, down upon the first, .to bite engagement.

The articulator closing stop is then adjusted to the technician to ..pro-

they are conformed to and fitted upon the patients jaws the desired external facial contour will be produced.

The key 29 may be made a permanent part of the tracer, such as by making it a fixed part of gear 25 and its shaft 26, in which case it is molded into the wax and usually turned slightly as the wax hardens, to free it for later operation.

What we claim is:

1. An lntra-oral tracer of the character described, comprising a body member externally of such shape as to enable it by molding to be attached in fixed position to a dental bite plate, a.

3. A tracer of the character described in claim 1, in which said body member is provided with an inner chamber, into which the tracer member extends, and including operating connections between operator and tracer member enclosed within said chamber, said operator being detachably connected to said operating connections.

4. A tracer of the character described in claim 1 wherein means is provided for causing said straight line movement of said tracer member including a pair of coacting bevelled members one of which is mounted on said tracer member and the other of which has a detachable connection with said operator.

FAY E. SMITH. DELMAR LACER. CLARION B. McLEOD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,776,474 Messerman Sept. 23, 1930 2,176,575 Sorenson Oct. 17, 1939

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